c++ - How to correctly notify in QQmlListProperty properties? -


whenever creating q_property later use in qml created notify signal tell qml data changed , needs reevaluated.

now having q_property of type qqmllistproperty<t> how can signalize item has been modified, added or removed?

is possible?

if have list there can't propertychanged() signal, because object reference stored remain same.
within list there won't properties, no signal emitted.

you instead use descendent of qabstractlistmodel designed handle problem, wrapping methods append, insert etc. in own methods, emit datachanged signal carries information necessary find changes.

of course implement similar wrapping qlist in object, has signal inform of data change. won't integrate nicely qml real model, @ least view update automatically, when datachanged signal received, , update necessary.

not so, if model of view changed directly, might happen, if manually call modelchanged(). in case, view miss information changed parts, recreate completely.


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